The first camp that you have to visit is the one just below the Statue of the Seven. Teleport there and drop down to the side and interact with the book in the camp.
"So far, so smooth. The weather is fine, supplies are plentiful, and the monsters have been on their best behavior..."
"I also discovered a Volume 6 of "The Boar Princess" in my backpack. Joel must've sneaked it in there. That cheeky kid..."
"Still, this book is about a brave Boar Princess and her journey up a snowy mountain with her companions... Well, I'm heading up a snowy mountain myself, and considering how well everything's gone so far... Who knows? Maybe this book is bringing me good luck. Thank you, Joel."
"Anyway, I shall be heading off to the next campsite to resupply and record my progress, and then I'll head down the mountain. Joel is waiting for me, after all."
The second camp is on the western area. Interact with the book in the camp to progress with the quest.
"Nothing untoward happened on the way here. The weather remains fine indeed. It seems that my luck has turned at last."
"Perhaps I can make a run for the summit after all..."
"I'll just give it a little go. If anything happens, I'll turn back right away."
The last camp spot is inside a cave, just across the Statue of the Seven. There is a breakable rock wall that you can destroy when you're in the cave, not far from the entrance. Interact with the last journal to get the last piece of the story.
"The snowstorm from the summit came too quickly. I barely had enough time to duck into this cave. I lost half my supplies in the chaos, too..."
"I don't know why, either, but the rocks above the cave collapsed suddenly, sealing the entrance with the falling gravel. This is very bad..."
"But... I believe that there's another way out for me. The other end of this cave is a cliff, yes, but there's nothing below but thick snow. If I try climbing a certain distance down and then jumping the rest of the way..."
"My supplies won't last more than a few more days. I have to act soon..."
"I promised Joel that I'd take him to see the snow. I won't break that promise."
"Oh, yes. If anyone sees these notes, please put some food into that feeding bowl for those foxes."
"They kept me company the entire time I was trapped in here. If I get the chance, I'd love to bring Joel back here to see them..."
After interacting with the last journal, you are able to put food down into the bowl to feed the foxes. It requires 2 berries. You can put food down once a day. After feeding the foxes about 5 or 6 times, you will get the "Untellable Tale" achievement, and a treasure chest with a crimson agate.